一、儲能變流器是雙向還是單向

儲能變流器（PCS）又稱儲(chu)能(neng)(neng)(neng)逆(ni)變器，是連接儲(chu)能(neng)(neng)(neng)電(dian)(dian)(dian)池(chi)系(xi)(xi)統和(he)電(dian)(dian)(dian)網(wang)的(de)雙(shuang)向電(dian)(dian)(dian)流可控轉(zhuan)換裝置(zhi)，能(neng)(neng)(neng)夠(gou)在電(dian)(dian)(dian)網(wang)和(he)儲(chu)能(neng)(neng)(neng)系(xi)(xi)統間(jian)精確(que)快速地調節電(dian)(dian)(dian)壓、頻率(lv)、功率(lv)，實(shi)現恒功率(lv)恒流充放電(dian)(dian)(dian)以(yi)及平滑波(bo)動(dong)性電(dian)(dian)(dian)源(yuan)輸(shu)出(chu)。

儲(chu)能(neng)變流(liu)(liu)(liu)器不(bu)僅能(neng)滿足傳統并網(wang)變流(liu)(liu)(liu)器對(dui)直流(liu)(liu)(liu)電轉換為交流(liu)(liu)(liu)電的(de)逆變要求，還可滿足儲(chu)能(neng)系統“充電+放電”帶來(lai)的(de)雙向變流(liu)(liu)(liu)需(xu)求，具有對(dui)電池充電和放電功能(neng)，可用(yong)于光(guang)伏(fu)、風力發(fa)電功率(lv)平滑(hua)、削峰填谷、微型電網(wang)等(deng)多種(zhong)場合(he)。

并網模式(shi)下，在(zai)負荷低谷期，儲能變流(liu)(liu)器把(ba)電(dian)(dian)網的交(jiao)流(liu)(liu)電(dian)(dian)整流(liu)(liu)成直流(liu)(liu)電(dian)(dian)給電(dian)(dian)池組充電(dian)(dian)，在(zai)負荷高峰(feng)期，儲能變流(liu)(liu)器把(ba)電(dian)(dian)池組中(zhong)的直流(liu)(liu)電(dian)(dian)逆(ni)變成交(jiao)流(liu)(liu)電(dian)(dian)反送到電(dian)(dian)網中(zhong)。

離網模(mo)式下，儲能變流器與主(zhu)電(dian)網脫(tuo)開，給本地的(de)部分負荷提供滿足電(dian)網電(dian)能質(zhi)量要求的(de)電(dian)能。

二、雙向儲能變流器的工作模式有哪些

雙向儲能變流器pcs的工作模(mo)(mo)式(shi)分為并網模(mo)(mo)式(shi)、離網模(mo)(mo)式(shi)和混合模(mo)(mo)式(shi)。

1、并網模式

并(bing)網模式下(xia)包括充(chong)電(dian)(dian)功能和(he)放電(dian)(dian)功能，此(ci)時用(yong)戶可以(yi)選擇(ze)自(zi)動模式和(he)手動模式。在(zai)自(zi)動模式下(xia)，如(ru)果(guo)用(yong)戶選擇(ze)并(bing)網充(chong)電(dian)(dian)或(huo)放電(dian)(dian)狀(zhuang)態，儲(chu)能逆(ni)變器將以(yi)之前設定好的值對蓄(xu)電(dian)(dian)池(chi)進行充(chong)電(dian)(dian)或(huo)放電(dian)(dian)。在(zai)手動模式下(xia)，用(yong)戶可以(yi)通過手動修改充(chong)電(dian)(dian)或(huo)放電(dian)(dian)電(dian)(dian)流、電(dian)(dian)壓和(he)時間值，使儲(chu)能逆(ni)變器工作在(zai)設定的充(chong)電(dian)(dian)或(huo)放電(dian)(dian)狀(zhuang)態。

并網模式中，儲能逆變器連接在一個大容量公用電網中，大容量是指該電網的總容量至少比儲能逆變器容量大10倍以上。并網模式的主要特征是儲能逆變器必(bi)須與(yu)存在(zai)的電(dian)網(wang)頻率(lv)同(tong)步。要做到與(yu)電(dian)網(wang)同(tong)步，儲(chu)能(neng)(neng)逆(ni)(ni)變器(qi)相對(dui)于(yu)電(dian)網(wang)來說(shuo)作為一個電(dian)流(liu)源(yuan)。有些情況下(xia)，儲(chu)能(neng)(neng)逆(ni)(ni)變器(qi)必(bi)須能(neng)(neng)通過無功控制為電(dian)網(wang)提供電(dian)壓支持。該模式常(chang)用于(yu)削(xue)峰填谷、電(dian)力負載平(ping)衡和調節電(dian)能(neng)(neng)質量。

2、離網模式

孤(gu)島(dao)系(xi)統(tong)(tong)是(shi)一(yi)個(ge)或(huo)多個(ge)發(fa)電(dian)(dian)(dian)系(xi)統(tong)(tong)并聯形成(cheng)一(yi)個(ge)局(ju)部(bu)的“微網(wang)(wang)”。孤(gu)島(dao)系(xi)統(tong)(tong)的主要特(te)征是(shi)局(ju)部(bu)電(dian)(dian)(dian)網(wang)(wang)與(yu)所(suo)有的大(da)電(dian)(dian)(dian)網(wang)(wang)脫(tuo)離(li)，儲能(neng)系(xi)統(tong)(tong)的額(e)定功率(lv)(lv)與(yu)局(ju)部(bu)電(dian)(dian)(dian)網(wang)(wang)產生(sheng)的總功率(lv)(lv)大(da)致相等。在(zai)(zai)這個(ge)系(xi)統(tong)(tong)中，儲能(neng)系(xi)統(tong)(tong)必須可以充當網(wang)(wang)路電(dian)(dian)(dian)源，給(gei)局(ju)部(bu)電(dian)(dian)(dian)網(wang)(wang)提供(gong)電(dian)(dian)(dian)壓和頻(pin)率(lv)(lv)控制。另一(yi)方面(mian)，如果(guo)一(yi)個(ge)發(fa)電(dian)(dian)(dian)裝置(zhi)不能(neng)與(yu)其他(ta)發(fa)電(dian)(dian)(dian)裝置(zhi)同步(bu)，比如一(yi)個(ge)柴油發(fa)電(dian)(dian)(dian)機連接在(zai)(zai)局(ju)部(bu)電(dian)(dian)(dian)網(wang)(wang)上，那么儲能(neng)系(xi)統(tong)(tong)必須作為(wei)(wei)一(yi)個(ge)電(dian)(dian)(dian)源之同步(bu)。有些情況(kuang)下(xia)，儲能(neng)系(xi)統(tong)(tong)還要在(zai)(zai)作為(wei)(wei)電(dian)(dian)(dian)源和與(yu)發(fa)電(dian)(dian)(dian)裝置(zhi)同步(bu)之間轉換。

孤(gu)島系統的特征是儲(chu)能系統與局(ju)部電網(wang)相連，這(zhe)些情形可(ke)能存在(zai)于(yu)偏遠山區或小島嶼。常見應用包括平滑(hua)由可(ke)變電源可(ke)變負載引起的功率波(bo)動，穩定電網(wang)，優化燃(ran)料(liao)的使用和調(diao)節(jie)電能質(zhi)量。

3、混合模式

儲能(neng)系(xi)統(tong)能(neng)夠在并網(wang)(wang)(wang)(wang)(wang)(wang)模式和離網(wang)(wang)(wang)(wang)(wang)(wang)模式之間進行切換。儲能(neng)系(xi)統(tong)處于微網(wang)(wang)(wang)(wang)(wang)(wang)中(zhong)，微網(wang)(wang)(wang)(wang)(wang)(wang)與(yu)公共電網(wang)(wang)(wang)(wang)(wang)(wang)接(jie)，正常(chang)工作狀態下作為(wei)(wei)并網(wang)(wang)(wang)(wang)(wang)(wang)系(xi)統(tong)運行如(ru)果微網(wang)(wang)(wang)(wang)(wang)(wang)與(yu)公共電網(wang)(wang)(wang)(wang)(wang)(wang)脫離，儲能(neng)系(xi)統(tong)將(jiang)工作在離網(wang)(wang)(wang)(wang)(wang)(wang)模式為(wei)(wei)微網(wang)(wang)(wang)(wang)(wang)(wang)提供主電源。常(chang)見應用包括濾波(bo)，穩(wen)定(ding)電網(wang)(wang)(wang)(wang)(wang)(wang)，調節電能(neng)質量和創造自愈網(wang)(wang)(wang)(wang)(wang)(wang)。